There is a common assumption that evolutionary explanations of religion undermine religious beliefs. Do etiological accounts similarly affect the rationality of religious practices? To answer this question, this paper looks at two influential evolutionary accounts of ritual, the hazard-precaution model and costly signaling theory. It examines whether Cuneo’s account of ritual knowledge as knowing to engage God can be maintained in the light of these evolutionary accounts. While the evolutionary accounts under consideration are not metaphysically incompatible with the idea that religious rituals engage God, they cast doubt on whether many, if not all, rituals can do this successfully.